Thermal mass flow meter

About: Thermal mass flow meter is a research topic. Over the lifetime, 1759 publications have been published within this topic receiving 21878 citations.

Wide range, high accuracy flow meter

Abstract: A turbine type flow meter incorporating an auxiliary turbine ahead of the main turbine, the auxiliary turbine rotating in the opposite direction from that of the main turbine and serving as a flow conditioner, thereby extending the effective range of the flow meter to lower rates of flow.

Apparatus and method for continuously measuring mass flow

Abstract: An apparatus and method for measuring mass flow rate which utilizes a pair of parallel conduits having fixed ends. A driving mechanism is connected between the conduits near their mid-point for applying transverse oscillations to the conduits at a selected frequency. The fluid whose mass flow rate is to be measured is divided roughly equally and supplied through the parallel conduits. A motion sensor upstream of the driving mechanism and another one downstream of the driving mechanism produce signals which have the same frequency as the driving frequency but which lead or lag the driving frequency with regard to phase. This difference in phase is a measurement of mass flow rate. The apparatus can be constructed to self compensate for changes in temperature and/or thermal gradients.

Apparatus and method for self-calibration of mass flow controller

Abstract: A mass flow sensor calibrator employs a variable-flow fluid source, a receptacle of known volume, and a pressure differentiator. The variable-flow fluid source supplies gas at varying rates to the mass flow sensor being calibrated and at proportional rates to a receptacle of known volume. A pressure differentiator computes the time derivative of gas flow into the receptacle of known volume and, from that, the actual flow into the receptacle. Given the actual flow, the proportionate flow into the mass flow sensor may be determined and the flow signal from the mass flow sensor correlated to the actual flow.

Sensor mounting for vibrating structures

Abstract: A Coriolis mass flow meter apparatus for determining the mass flow rate of fluids passed through twin flow tubes which are vibrated by a driver in a tuning fork fashion so as to be distorted by the mass flow rate of the fluid passing through the tubes with the distortion measured by sensors; where, sensor and driver components are mounted to each of the flow tubes so that the masses of the components and the structures used to mount the components to the flow tubes results in a center of gravity which is located on the axes about which each flow tube is distorted by generated Coriolis forces. The electrical interconnection between the sensor and driver components mounted on flow tubes and a non-vibrated structure (72) is provided by wires suspended between the flow tubes and non-vibrating structure in a half-loop shape.

Air flow metering apparatus for internal combustion engines

Abstract: An air flow metering apparatus for measuring a suction air flow fed to an internal combustion engine comprises at least two Karman' vortex type air flow meters disposed separately in at least two air suction passages, respectively. The output signals from the flow meters are switched in such manner that in a predetermined range of high air flow rates, the output signal from one of the flow meter is utilized for measuring or sensing the air flow rate, while in a predetermined low flow rate range, the output signal from the other flow meter is utilized for the same purpose. Alternatively, in a predetermined low flow rate range, only one of the air suction passages is employed, while both of the air suction passages are employed in a predetermined range of high air flow rates. The air flow metering apparatus assures the detection or measurement of the suction air flow rate over a whole operation range of the engine with a high reliability and enhanced accuracy.